Closed Kinetic Chain Research Articles

The effects of open/closed kinetic chain exercises in water on the electrical activity of selected lumbar muscles, lumbopelvic control, ground reaction force and psychological factors in men with chronic non-specific low back pain: A study protocol for a randomized clinical trial

Background and aimResearch has documented chronic non-specific low back pain (CNSLBP) as one of the primary causes of absenteeism at work, often accompanied by the use of health insurance and healthcare services. Considering little research on the consequences of open/closed kinetic chain (O/CKC) exercises in water on CNSLBP improvement, the present study is to investigate the effects of such interventions on the electrical activity of selected lumbar muscles, pain, lumbopelvic control (LPC), ground reaction force (GRF), and psychological factors in men with CNSLBP. Materials and methodsThis is a randomized controlled trial that involves individuals with CNSLBP between the ages of 40 and 60 years. Participants are randomly assigned, using block randomization, to one of the following groups: open kinetic chain (OKC) exercises, closed kinetic chain (CKC) exercises, or controls. The training groups engage in the exercises for eight weeks, with three sessions per week and 60 min each at the University of Bu-Ali Sina pool, following the prescribed workout routine. The primary outcomes of the electrical activity of the multifidus (MF), transversus abdominis (TrA), gluteus medius (GM), and quadratus lumborum (QL) muscles are measured by an electromyography (EMG) device. Additionally, the pressure biofeedback (BFB) device and the visual analog scale (VAS) are utilized to assess LPC and pain intensity, respectively. The secondary outcomes of the GRF, along with foot pressure and kinesiophobia, are subsequently measured by the Tampa Scale of Kinesiophobia (TSK). ConclusionBy comparing the outcomes between the OKC exercise group, CKC exercise group, and control group, this study aims to determine the differential effects of these two water-based exercise interventions on the various physical and psychological parameters in individuals with CNSLBP. The findings provide valuable insights into the most effective approach to water-based rehabilitation for individuals with CNSLBP. By comparing the outcomes of OKC and CKC exercises, healthcare professionals can make informed decisions when designing tailored rehabilitation programs for this patient population. The results also contribute to the development of evidence-based guidelines for the management of CNSLBP using water-based exercises.

The Effects of Open and Closed Kinetic Chain Exercises on Visual Reaction Times and Certain Motor Skills in Young Male Boxers

This study aimed to determine the effects of open kinetic chain (OKC) and closed kinetic chain (CKC) exercises on visual reaction times and certain motor skills in young male boxers. Twelve young male athletes (mean age: 16.92±1.08 years) voluntarily participated in this study, which employed a pretest-posttest experimental research model, a quantitative research method, without a control group. The Ethics Committee Approval required for the research was received from Muş Alparslan University Scientific Research and Publication Ethics Committee with decision number 9/73 dated 08.11.2023. Prior to and following training in OKC and CKC exercises, the athletes were tested on visual reaction times, vertical jumping, and flexibility. The paired samples t-test was applied to normally distributed data. According to our findings, there were no significant differences in the visual reaction time and flexibility tests with respect to the pre- and post-test results for the OKC exercises (p ˃ .05), although a significant difference was detected for the vertical jump test (p ˂ .05), with the post-test values determined to be lower than the pre-test values. While there were no significant differences in the CKC exercise pre-and post-test results for the vertical jump and flexibility tests (p ˃.05), a significant difference was observed in the visual reaction test (p ˂ .05), for which the post-test values were lower than the pre-test values. Based on these results, OKC exercises were determined to have a negative impact on jumping ability, whereas CKC exercises exhibited positive effects on visual reaction times. The use of CKC exercises can thus be recommended for studies aimed at improving visual reaction performance in young male boxers.

Acute effect of an intervention with open and closed kinetic chain muscle strength exercises on postural control and muscle power in elderly people: A randomized clinical trial

IntroductionAging causes changes in stance control and muscle function. However, strength exercises can mitigate these negative effects. Intervention practices are classified into open kinetic chain (OKC) and closed kinetic chain (CKC), but it is unclear whether there are differences between them regarding muscle power and balance in the older people. Thus, this study aimed to investigate the acute effect of an intervention in OKC and CKC on stance control and muscle power in the older people. MethodsThis study is a randomized clinical trial. A total of 29 older people participated in this study, divided into 3 groups: control group (CG) (n = 9), open kinetic chain group (OKCG) (n = 10), and closed kinetic chain group (CKCG) (n = 10). Stance control was evaluated on a force platform under bipedal, semi-tandem, and unipedal support conditions. Muscle power assessed based on the time to perform the sit-to-stand test (STS). The acute intervention in OKC and CKC consisted of 2 exercises for each intervention group. ResultsThere was no difference between acute interventions in OKC and CKC on stance control and muscle power. The time in STS was shorter in the CKCG compared to the CG. The largest oscillations of the center of pressure (COP) were found in the unipedal stance condition. ConclusionAn acute intervention in OKC and CKC did not differentiate stance balance and muscle power in the older people. However, CKC exercises are more effective for functional tasks than OKC exercises. The greater complexity of the task (unipedal support) causes greater stance oscillations in the older people.

Effect of open vs. closed kinetic chain exercises in ACL rehabilitation on knee joint pain, laxity, extensor muscles strength, and function: a systematic review with meta-analysis.

PROSPERO [CRD42023475230].

The Relationship of Open- and Closed-Kinetic-Chain Rate of Force Development With Jump Performance Following Anterior Cruciate Ligament Reconstruction.

To determine between-limbs differences in isometric rate of force development (RFD) measured during open- (OKC) and closed-kinetic-chain (CKC) strength testing and establish which method had the strongest relationship to single-leg vertical-jump performance and knee mechanics after anterior cruciate ligament (ACL)reconstruction. Subjects (n = 19) 1 to 5years from ACL reconstruction performed isometric knee extensions (OKC), unilateral isometric midthigh pulls (CKC), and single-leg vertical jumps on the ACL-involved and -noninvolved limbs. Between-limbs differences were assessed using paired t tests, and the relationship between RFD, jump performance, and knee mechanics was assessed using correlation coefficients (r; P ≤ .05). There were significant between-limbs differences in OKC RFD (P = .008, d = -0.69) but not CKC RFD. OKC RFD in the ACL-involved limb had a strong association with jump height (r = .64, P = .003), knee-joint power (r = .72, P < .001), and peak knee-flexion angle (r = .72, P = .001). CKC RFD in the ACL-involved limb had a strong association with jump height (r = .65, P = .004) and knee-joint power (r = .67, P = .002) but not peak knee-flexion angle (r = .40, P = .09). While both OKC and CKC RFD were strongly related to jump performance and knee-joint power, OKC RFD was able to detect between-limbs RFD asymmetries and was strongly related to knee-joint kinematics. These findings indicate that isometric knee extension may be optimal for assessing RFD after ACL reconstruction.

The Comparison Close Kinetic Chain Exercise And Open Kinetic Chain Exercise After Infra Red To Increasing Functional Ability In Primary Osteoarthritis Genu At Bhayangkara Kediri Hospital

Osteoarthritis is a degenerative health disorder characterized by stiffness and inflammation of the joints, characterized by damage to the cartilage, which can cause pain in the joints of the hands, neck, back, lower body, back and often the knee joints. Pain in genuine osteoarthritis can last a long time causing limitations in the ability to function functional activities. One non-pharmacological method is kinetic chain exercise. This study aims to determine the comparison of close kinetic chain exercise and open kinetic chain exercise after giving infrared to increase functional ability in conditions of primary genu osteoarthritis. This research uses a quasi experimental design with a pre and post test two group design approach. The sample for this research was 30 respondents. 15 respondents were treated with close kinetic chain exercise after giving infrared and 15 respondents were treated with open kinetic chain exercise after giving infrared. There is an effect of close kinetic chain exercise after administering infrared on increasing functional ability in primary genu osteoarthritis conditions at Bhayangkara Kediri Hospitalwith a significance of 0.001&lt; α (α=0.05).There is an effect of open kinetic chain exercise after administering infrared on improving functional abilities in primary genu osteoarthritis conditions at Bhayangkara Kediri Hospital with a significance of 0.006&lt; α (α=0.05).There is a difference in the effect of close kinetic chain exercise after giving infrared and open kinetic chain exercise after giving infrared on increasing functional ability in primary genu osteoarthritis conditions at Bhayangkara Kediri Hospital with a significance value of 0.035&lt; α (α=0.05). Close kinetic chain exercise after giving infra red is more effective than open kinetic chain exercise after giving infra red in improving the ability of primary genu osteoarthritis conditions at Bhayangkara Kediri Hospital in 2023.

PERBEDAAN PENGARUH OPEN KINETIC CHAIN EXERCISE DAN CLOSE KINETIC CHAIN EXERCISE TERHADAP KEKUATAN OTOT QUADRICEPS FEMORIS PASCA OPERASI ANTERIOR CRUCIATE LIGAMEN DITINJAU DARI USIA

This research is an experimental research. The sample is post-Anterior Cruciate Ligament surgery patients at the Solo Sport Physiotherapy Clinic as many as 16 people including Open and Close exercise categories and based on adolescent and adult age categories. Samples were taken using purposive sampling technique. The variables in this study include: 1) Quadriceps Femoris Muscle Strength (Y); 2) Open Exercise (a1); 3) Close Exercise (a2); and 4) Age (b). Research data were obtained from measurements using an Electromyograph. Hypothesis testing using two-way Anova test and t test. Conclusion, (1) There is a difference in the effect of quadriceps femoris muscle strength after being given open kinetic chain and close kinetic chain exercises in ACL postoperative patients. Which means that close kinetic chain training has a better improvement than open kinetic chain in ACL postoperative patients. (2) There are differences in the effect of quadriceps femoris muscle strength in adolescent and adult athletes. Which means that adult athletes have a better increase in quadriceps femoris muscle strength compared to adolescent athletes. (3) There is no interaction between open kinetic chain and close kinetic chain training methods with adolescent and adult age on increasing quadriceps muscle strength.

Variability of unilateral and bilateral isometric muscle strength of lower extremities extensors in young females and males.

The muscle strength of the lower extremity extensors can be evaluated in the closed kinetic chain (CKC) during unilateral or bilateral conditions. Factors such as the mass and length of the muscle, joint angle, type of contraction, and gender influence the magnitude of the muscle strength. The aim of this study was to compare the isometric strength of lower extremity extensors between the different knee extension angles (KEs) as well as between bilateral and unilateral conditions. Nineteen female students (age: 20.2 ± 0.6 years) and nineteen male students (age: 20.3 ± 0.7 years) participated in the study. The muscle strength was evaluated in CKC using the strain gauge dynamometer. The analysis included values of the maximum muscle strength normalized to body mass (MS/BM) for the six KEs of 80°, 70°, 60°, 50°, 40° and 30°. A significant main effect in the MS/BM values for the angle factor (p < 0.001) and condition factor (p < 0.001) was found. Moreover, there was a non-significant interaction effect between the angle factor and gender factor (p = 0.476) as well as between the condition factor and gender factor (p = 0.770). Comparisons showed significant differences in the MS/BM values between the six KEs (p < 0.001). Furthermore, significantly lower MS/BM values for bilateral conditions than unilateral conditions at the 30° KE were observed (p < 0.001). The decrease in KE by 10° significantly increased the muscle strength of the lower extremity extensors. Gender did not affect the change in MS/BM values with the change in KE and conditions. Findings also revealed significant bilateral deficit, i.e., significantly a lower summed muscle strength during bilateral conditions than unilateral conditions. The study emphasized the importance of selecting the 30° KE as the optimal angle to assess the maximum strength developed in CKC.

Effectiveness of open and close kinetic chains after anterior cruciate ligament reconstruction: A systematic review and meta-analysis

Background: The Anterior Cruciate Ligament (ACL) is a ligament that has the function to maintain the stability of the knee so that it does not shift excessively towards the front. ACL injuries are injuries that are often experienced by sports athletes, especially those who often make fast and sudden movements. There are non-operative and operative methods for treating ACL. Non-operative methods are considered less effective because they usually require a slightly longer recovery period. One of the most frequently used surgical methods is reconstruction. After reconstruction, there is a need for exercises to speed up recovery and improve its function. Some examples of exercises that can be used are Open Kinetic Chain (OKC) and Close Kinetic Chain (CKC) exercises.Purpose: To determine the level of effectiveness between OKC and CKC for individual after ACL reconstructionMethod: This research was a systematic review and meta-analysis with the PRISMA diagram to filter supporting articles. To assess the quality of Randomized Controlled Trial (RCT) design studies, the Critical Appraisal Checklist was used. Meanwhile, the Characteristics for Included Studies were used to assess the feasibility. The article search came from the Pubmed database with the keywords "Close Kinetic Chain" AND "Open Kinetic Chain" AND "Anterior Cruciate Ligament" AND "Reconstruction". Inclusion criteria were full text articles in Indonesian or English with an RCT study design. The relationship measure used was Mean Difference, and Revman 5.4. was used for analysis.Results: There were five articles from UK, US and Turkey for this study. The results of the study showed that there was an increasing effect after carrying out OKC and CKC exercises. However, the difference in exercise benefits between OKC and CKC exercises was not notably significant, which were shown by a p-value &gt;0.05 (MD= -1.66; 95% CI=-18.71 to 5.42; P=0.65).Conclusion: OKC and CKC exercises had been proven to have an effect on improving ACL recovery after reconstruction, but the difference in effect between OKC and CKC had not been found.

Acute effect of open and closed kinetic chain training on lower limb muscle strength in young adults

Among training prescription variations for improving muscle strength, we can highlight open kinetic chain (OKC) and closed kinetic chain (CKC) exercises. The aim of this study was to investigate the acute effect of OKC and CKC exercises on lower limb muscle strength in young adults. Subjects were invited to participate in an acute training consisting of three OKC exercises and three CKC exercises and performed three sets of ten repetitions. To evaluate the torque and muscle power, an isokinetic dynamometer and a force platform were used. The analyzed variables were: peak of torque, time to peak torque, mean power and average power. Univariate analyses were used to compare the performance of participants in OKC and CKC exercises in torque and power tests. Peak torque was higher in the extensor and plantar flexion movements than knee and ankle joints, respectively. When comparing OKC and CKC exercises, OKC exercises produced a higher peak of torque and mean power in all the joints than CKC. We concluded that OKC exercises can be used for improving strength in young adults.

The Effects of a Novel Lateral Ankle Strengthening Program in NCAA Division III Football Players

Introduction: Lateral ankle sprains (LAS) are among the most reported injuries in college athletics, typically resulting from excessive closed-kinetic chain (CKC) supination. The purpose of this study was to compare the effects of a novel CKC supination-style ankle strengthening program to a traditional ankle strengthening program on common LAS indices. Methods: Thirty NCAA Division III collegiate football players (19.9±1.0yrs., 182.2±6.9cm, 98.8±18.0kg) were randomly assigned to a novel exercise (SUP, n = 16) or traditional exercise group (TRA, n = 14). The SUP group performed dynamic bodyweight exercises with controlled ankle supination while the TRA group performed traditional ankle strengthening exercise using elastic bands and stability exercises 3 times per week for 6 weeks. Right and left ankle inversion (InvR, InvL) and eversion (EvR, EvL) strength (kg), ankle inversion range of motion (romR, romL) (deg.), and figure-8 hop test (fig8R, fig8L) (s) performance were assessed pre- and post-intervention. Results: Both groups showed significant improvements in all outcome measures pre- to post-test (ΔInvR: TRA 4.5±4.3kg, SUP 5.0±4.4kg; ΔIvL: TRA 4.0±3.8kg, SUP 4.8±3.6kg; ΔEvR: TRA 5.7±4.3kg, SUP 4.7±3.3kg; ΔEvL: TRA 4.7±2.9kg, SUP 4.5±2.2kg; ΔromR: TRA 4.5±2.6°, SUP 4.9±3.0°; ΔromL: TRA 4.7±4.5°, SUP 4.6±5.1°; Δfig8R: TRA -0.43±0.20s, SUP -0.37±0.31s; Δfig8L: TRA -0.40±0.22s, SUP -0.34±0.30s; p’s&lt;0.001), with no difference between groups. Conclusions: A bodyweight, supination style ankle training program can improve physical qualities related to LAS to a similar extent as a traditional program, and therefore, could potentially be a viable alternative strategy for reducing LAS in Division III NCAA football players.

Loaded open-kinetic-chain exercises stretch the anterior cruciate ligament more than closed-kinetic-chain exercises: In-vivo assessment of anterior cruciate ligament length change

BackgroundUsage of open-kinetic-chain (OKC) or closed-kinetic-chain (CKC) exercises during rehabilitation planning after anterior cruciate ligament (ACL) reconstruction has been debated for decades. However, the ACL elongation pattern during different rehabilitation exercises at different loadings remains unclear. ObjectivesThis study aimed to determine the effects of OKC and CKC exercises on the length of ACL anteromedial bundle (AMB) and posterolateral bundle (PLB) to provide biomechanical support for making rehabilitation schedules. DesignLaboratory Descriptive Study. MethodEighteen healthy volunteers were asked to perform two OKC motions, including non-weight-bearing and 10 kg loaded seated knee extension (OKC-0, OKC-10), as well as two CKC motions, including box squat (BS) and deep single-legged lunge (Lunge). Techniques of 2D-to-3D image registration and 3D ligament simulation were used to quantify length changes of ACL. ResultsThe motion which led to the least and most ACL elongation were OKC-0 and OKC-10, respectively. The AMB and PLB were significantly longer in OKC-10 than those in OKC-0 during 0–60° and 0–55° of knee flexion (p < 0.01). Compared with reference length, the AMB and PLB were stretched during 0–30° and 0–10° respectively during OKC-10. During CKC exercises, the AMB and PLB were also stretched from 0 to 25°and 0–5°, respectively. Additionally, no significant difference was found in the length change of ACL bundles between BS and lunge. ConclusionsOKC-0 may be safe for the rehabilitation program after ACL reconstruction, and loaded exercises shall be applied when restricted with >30° in early-stage rehabilitation.

Open Versus Closed Kinetic Chain Exercise: a Comparison of Walking Capacity in Chronic Post-Stroke Phase

Introduction: The chronic post-stroke phase is often accompanied by various sensory, cognitive, motoric, coordination, and balance impairments. Decreased strength and motoric control contribute to walking capacity in patients with stroke. This study aims to evaluate the effect of Open Kinetic Chain (OKC) vs Closed Kinetic Chain (CKC) exercise on walking capacity in the chronic post-stroke phase. Open Kinetic Chain (OKC) and Closed Kinetic Chain (CKC) were reported to improve functional mobility and balance in the chronic post-stroke phase. However, there is a lack of studies emphasizing the effect of OKC and CKC on walking capacity.&#x0D; Methods: This study is a quasi-experimental pre- and post-controlled trial group design. Twenty subjects were randomized into two groups of equal size: the CKC group (n=10) and the OKC group (n=10). There was one subject from each group who dropped out at the end of the study. CKC and OKC groups were trained for 6 weeks. The walking capacity was measured with 2 Minutes Walking Test (2WMT).&#x0D; Results: 2WMT results showed improvement in both groups after 6 weeks of intervention, 56,17 ± 10,95 ± to 57,43 ± 11,29 in CKC group (p&lt;0.001) and 57,04 ± 8,58 to 58,19 ± 8,77 in OKC group (p&lt;0.002).&#x0D; Conclusion: CKC and OKC exercise significantly improve the 2WMT results after 6 weeks of intervention.&#x0D; Keywords: Chronic post-stroke phase, walking capacity, open kinetic chain exercise, closed kinetic chain exercise

Open Versus Closed Kinetic Chain Exercise: a Comparison of Walking Capacity in Chronic Post-Stroke Phase

ABSTRACTIntroduction: The chronic post-stroke phase is often accompanied by various sensory, cognitive, motoric, coordination, and balance impairments. Decreased strength and motoric control contribute to walkingcapacity in patients with stroke. Open Kinetic Chain (OKC) and Closed Kinetic Chain (CKC) were reported to improve strength, functional mobility and balance in the chronic post-stroke phase. However, there is aphysiologically differences between CKC and OKC exercise. This study aims to compare the result of two methods of progressive resistant training (PRT) on walking capacity in the chronic post-stroke phase.Methods: This study is a quasi-experimental pre- and post-controlled trial group design. Twenty subjects were randomized into two groups of equal size: the CKC group (n=10) and the OKC group (n=10). Therewas one subject from each group who dropped out at the end of the study. CKC and OKC groups were trained for 6 weeks. The walking capacity was measured with 2 Minutes Walking Test (2WMT).Results: 2WMT results showed improvement in both groups after 6 weeks of intervention, while CKC group show greater improvement in walking distance 56,17 ± 10,95  to 57,43 compared to OKC group57,04 ± 8,58 to 58,19 ± 8,77 (p&lt;0.002).Conclusions: This study shows CKC group showed slightly better improvement in walking capacity after 6 weeks of progressive resistance training compare to OKC group. However, there were no statisticallydifferences between the groups

Effects of Open and Closed Chain Exercises on Dynamic Balance and Range of Motion in Patients with Knee Osteoarthritis: RCT

Background: Osteoarthritis is a combination of mechanical problems characterized by degradation of articular cartilage, articulating joints and subchondral space. Aim: To compare the effects of open chain kinetic exercises and closed kinetic chain exercises in improving dynamic balance and range of motion in patients with knee osteoarthritis. Study Design: Randomized controlled trial. Methodology: Study was conducted at Chugtai Medical center Lahore and sample of 46 patients were recruited and were randomly allocated in two groups. One group performed OKC exercises and the other group was asked to perform CKC exercises, while both of the groups received a common baseline treatment prior to corresponding intervention. Two session a week were given for a period of one month. Goniometry and Y-balance scale were used to assess ROM and dynamic balance pre and post treatment, respectively. Data was evaluated by using SPSS version 23. Results: In this study, the intra-group analysis illustrated that the increase in range of motion and improvement in dynamic balance was statistically significant in both groups with p-value&lt;0.05. Whereas, the inter-group analysis showed that both interventions were clinically effective in treating knee osteoarthritis with p-value&gt;0.05 during the treatment session of four weeks. Practical Implication: This study highlighted that physical training that includes open kinetic chain (OKC) and closed kinetic chain (CKC) exercises were found to be effective in improving balance and in increasing range of motion by reducing pain among osteoarthritis patients. Conclusion: It was concluded that patients with OKC exercises have shown equal improvement in ROM and dynamic balance compared to those who have been treated with CKC exercises. Keywords: Osteoarthritis, Exercises and Dynamic Balance.

A combined anterior cruciate ligament/Meniscal injury alters the patellofemoral joint kinematics of anterior cruciate ligament-deficient knees during a single-leg lunge exercise: A cross-sectional study.

Anterior cruciate ligament deficiency (ACLD) is often accompanied by concomitant meniscal tears. The study aimed to assess the kinematic alterations of patellofemoral joint (PFJ) in anterior cruciate ligament deficiency knees with or without meniscal tears during a single-leg lunge. Sixty unilateral anterior cruciate ligament deficiency patients were recruited for the study, including 15 isolated anterior cruciate ligament deficiency patients (group 1), 15 anterior cruciate ligament deficiency patients with medial meniscal tears (group 2), 15 patients with lateral meniscal tears (group 3) and 15 patients with combined medial/lateral meniscal tears (group 4). The patellofemoral joint kinematics were determined by a single fluoroscopic image system. Patellofemoral joint kinematics of contralateral anterior cruciate ligament-intact (ACLI) and anterior cruciate ligament deficiency knees were compared. With or without meniscal tears, anterior cruciate ligament deficiency knees had significantly smaller patellar flexion than the anterior cruciate ligament-intact knees (∼5°-10°; p < 0.05). anterior cruciate ligament deficiency knees had more patellar lateral tilting by approximately 1°-2° than the anterior cruciate ligament-intact knees (p < 0.05) in groups 2, 3, and 4. anterior cruciate ligament deficiency groups with medial meniscal deficiencies showed consistent increased lateral patellar translations (2-4mm) compared to the anterior cruciate ligament-intact group during a single-leg lunge. The results indicate that meniscal tears alter anterior cruciate ligament deficiency patients' patellofemoral joint kinematics and the types of the meniscal injuries also affect the patellofemoral joint kinematics. Considering the varying effects of meniscal tears on the patellofemoral joint kinematics, specific treatments for anterior cruciate ligament deficiency patients with meniscal tears should be proposed in some closed kinetic chain (CKC) exercise programs, such as single-leg lunge.

Effects Of Fatigue On Hamstring:quadricep Ratio And Neuromuscular Activation During Closed Kinetic Chain Exercises

PURPOSE: To examine the effects of fatigue on the hamstring:quadricep ratio and motor unitrecruitment during closed kinetic chain exercises. METHODS: Ten males (20.1 + 1.1 yrs) and ten females ( 21.2 + 2.1 yrs) cycled at 110% of theirPhysical Working Capacity Fatigue Threshold (PWCFT) until exhaustion (TTE). Participants alsoperformed three closed kinetic chain (CKC) exercises before (PRE) and after (POST) the TTE, includinga front lunge (FL), side lunge (SL), and single leg squat (SLSQ). Each of the four CKC exercises wereperformed twice PRE and twice POST. Electromyography (EMG) of the vastus lateralis (VL) and bicepsfemoris (BF) was recorded on the dominant leg. Raw EMG recordings were normalized to maximalvoluntary isometric contractions (MVICs) and analyzed for root mean square (RMS). Thehamstring:quadricep ratio (H:Q) was calculated using RMS as:BF/VL. Data were analyzed usingmixed-design repeated-measures ANOVA. RESULTS: During the FL, a main effect of time was observed for the H:Q (F = 10.199;p = 0.005) andRMS of the VL (F = 17.462;p < 0.001). Specifically, H:Q was lower at POST (0.388 + 0.081) comparedto PRE (0.451 + 0.091) and RMS of VL was higher at POST (33.435 + 3.113) compared to PRE (27.937+ 3.004). No main effect of time (F = 6.275;p = 0.22) for RMS of the BF was observed. During theSLSQ, a main effect of time was observed for the H:Q (F = 7.498;p = 0.014) and RMS of the VL (F = 13.380;p = 0.002). Specifically, H:Q was lower at POST (0.392 + 0.087) compared to PRE (0.527 + 0.119) and RMS of VL was higher at POST (50.683 + 4.056) compared to PRE (41.457 + 4.391). Nomain effect of time (F = 0.238;p = 0.632) was observed for RMS of the BF During the SL, a main effectof time was observed for H:Q (F = 7.526;p = 0.013) and RMS of the VL (F = 9.548;p = 0.006).Specifically, H:Q was higher at POST (0.493 + 0.097) compared to PRE (0.354 + 0.098) and RMS of VLwas lower at POST (37.24 + 1.072) compared to PRE (49.644 + 1.083). No main effect of time (F = 0.766;p = 0.392) was observed for RMS of the BF. CONCLUSIONS: Fatigue may impact the H:Q ratio during closed-kinetic chain exercises These datasuggest that changes in the H:Q ratio may be dependent on fatigue-related changes in motor unitrecruitment of quadricep muscles.

EFFECTS OF UNSTABLE SURFACE CLOSED KINETIC CHAIN EXERCISES ON HAMSTRING:QUADRICEP RATIO AND NEUROMUSCULAR ACTIVATION

PURPOSE: To examine the effects of performing closed-kinetic chain exercises on an unstable surface on the hamstring:quadricep ratio and motor unit recruitment in males and females. METHODS: Ten males (20.1 + 1.1 yrs) and ten females (21.2 + 2.1 yrs) performed closed kinetic chain exercises (CKCs) including a front lunge (FL), side lunge (SL), and single-leg squat (SLSQ). Each of the CKCs were performed twice on both a stable (SS) and unstable surface (US). Electromyography (EMG) of the vastus lateralis (VL) and biceps femoris (BF) was recorded on the dominant leg. Raw EMG recordings were normalized to maximal voluntary isometric contractions (MVICs) and analyzed for root mean square (RMS). The hamstring:quadricep ratio (H:Q) was calculated using RMS as: BF/VL. Data were analyzed using mixed-design repeated-measures ANOVA. RESULTS: No significant differences were observed between males and females during the FL (p = 0.666), SLSQ (p = 0.589), or SL (p = 0.768). During the FL, a main effect of condition was observed for H:Q (F = 10.832; p = 0.004) and RMS of VL (F = 17.462; p < 0.001) with a lower H:Q during US (0.362 + 0.072) compared to SS (0.48 + 0.1) and greater RMS of the VL during US (31.98 + 2.99) compared to SS (29.4 + 3.21). No main effect of condition for RMS of BF was observed (F = 0.184; p = 0.673). During the SLSQ, a main effect of condition was observed for H:Q (F = 12.662; p = 0.002) and RMS of VL (F = 6.646; p = 0.019), with lower H:Q during US (0.423 + 0.109) compared to SS (0.538 + 0.129) and greater RMS of VL during US (48.412 + 5.53) compared to SS (42.627 + 3.84). A main effect of condition was also observed for the BF (F = 14.983; p = 0 .001), with a significant decrease during US (15.051 + 3.56) compared to SS (20.631 + 4.51). During the SL, a main effect of condition was observed for H:Q (F = 8.909; p = 0.008) and RMS of VL (F = 75.454; p < 0 .001) with a greater H:Q during US (0.493 + 0.055) compared to SS (0.378 + 0.043) and lower RMS of VL during US (35.497 + 3.406) compared to SS (40.884 + 3.791). A main effect of condition was also observed for the BF (F = 17.808; p < 0 .001), with a significant increase during US (12.641 + 2.478) compared to SS (8.777 + 2.339). CONCLUSIONS: While no significant differences were observed between males and females, data suggest that performing CKCs on an unstable surface results in changes in H:Q and motor unit recruitment of the BF and VL.

Hip Fracture In A Healthy Collegiate Distance Runner Without Relevant Hip Symptoms

HX: A 20-year-old female Division I collegiate distance runner sustained a traumatic right femoral neck fx due to slipping while competing in the conference cross-country championships in February of 2021. She presented to AT and PT in the Spring of 2020 with bilateral, lateral knee pain consistent with ITBS. She had a history of metatarsal stress fx the previous season. The athlete had a normal DEXA scan, normal blood work, and self-reported no history of amenorrhea. PE: Pre-fracture, the athlete had full hip and knee AROM and PROM without pain. The athlete was able to run 40-50 miles per week without exacerbation of ITBS, including 10-12 mile long runs without symptoms. Athlete underwent uncomplicated ORIF following injury to stabilize the fracture. Bony healing was delayed until 7 months post-op. An athlete was making progress with rehab as expected through the end of the school year (3 months post-op) before returning home for summer. Upon returning to campus from summer vacation, the athlete had a plateau in her rehab process. She began to exhibit leg length discrepancy, pelvic position abnormalities, grossly limited AROM/PROM of hip extension and ER, significantly decreased strength of the R LE, and limited capsular mobility of the hip. DDX:Pre-injury-ITBS/TFL Strain-Vastus Lateralis Muscle Strain-FAIPost Injury-FAI-Scar tissue formation in posterior hip-CRPS-Lumbopelvic Dysfunction TESTS & RESULTS:-Multiple plain radiographs showing delayed healing until 7 months post-op-MSK US showing scar tissue formation at the greater trochanter near gluteus medius insertion and near the superior gluteal nerve-Bloodwork pending WORKING DIAGNOSIS: -Pathological Femoral Neck Fx w/delayed healing s/p ORIF w/ associated FAI secondary to lumbopelvic dysfunction TREATMENT AND OUTCOMES:The athlete performing dual and single limb lower extremity strengthening exercises including closed-kinetic chain w/resistance. She went through a return to walking/jogging protocol and was able to jog on the track for 400 m before the plateau in progress. She is currently performing dual-leg bodyweight bridges and basic leg lifts. The athlete is unable to perform single-leg bridges on right. AT and PT performing graded joint mobilizations to promote extension and external rotation.

Comparative Effects of Daily Adjustable Progressive Resistance Exercises Technique &amp; Close Kinetic Chain Exercises on Extensor Lag in Post-Operative Knee Stiffness

Background: Post-operative knee stiffness is caused by arthrofibrosis and functional limitation. Extensor lag is commonly prevalent after knee surgery. There are different approaches to treat this condition. Close kinetic chain exercises are hypothesized as one of effective treatment. DAPRE technique has remarked effects. Aim: To determine effects of DAPRE technique and close kinetic chain exercises on pain intensity, ROM, function, strength among post-operative knee stiffness. Study Design: Randomized control trial. Methodology: Total of 22 patients with post-operative knee stiffness were recruited and divided in two groups. One group received DAPRE technique and other group received close kinetic chain exercises were participated by using a Non-probability convenience sampling technique. Results: The result showed statistically significant difference in both groups in terms of NPRS, WOMAC index, ROM and strength with P-value less than 0.05. Conclusion: It was concluded that Close kinetic chain exercises was more effective than the Daily adjustable progressive resistance exercises on extensor lag for post-operative knee joint stiffness to improving the pain, physical function, range of motion and strength. Keywords: Knee Stiffness, Extensor Lag, Kinetic Chain Exercise, DAPRE and Resistance Exercises.